Mastitis is a serious problem within the milking industry and significant research has been conducted to ameliorate this problem. Mastitis is caused by bacteria infecting the mammary gland. Mastitis may be clinical (where there are visible signs of inflammation of the mammary gland or there are changes to the normal colour or consistency of milk); or mastitis may be subclinical where there is no visible changes to the mammary gland or milk.
Clinical mastitis when detected during lactation is normally treated with antibiotics. There is in addition to the cost of antibiotic treatment a requirement to with-hold the milk from supply, until it is clear of any antibiotic residues resulting in lost of milk income.
Subclinical mastitis is normally treated with dry cow antibiotic therapy at dry off. If clinical or subclinical mastitis is deemed un-curable; the animal is normally culled and sent to slaughter.
Both forms of mastitis results in significant financial loss to the farmer.
Therefore, it is best if practices can be put into place that prevent mastitis from occurring.
One such prevention method is the use of teat sanitisation or disinfection that prevents the contamination that occurs from one cow to another through using the same teat cups. Typically bacteria is deposited onto the teat skin by the contaminated teat cup and after milking occurs can migrate down to the teat end and enter the teat canal to cause a mastititic condition. This may occur as a consequence of being contacted with contaminated teat cups or merely from the environment in which the animals are kept.
Currently, there are two main methods by which teats are disinfected.
In countries that have smaller herds with high labour content, teats are disinfected by dipping teats in disinfectant.
The teat dipping process requires each teat to be dipped in turn until all four teats have been dipped.
In countries that have a lower labour content and larger herds (such as New Zealand and Australia) the teats are sprayed.
The teat spraying process involves spraying disinfectant on to all four teats at the same time and therefore this is less time consuming than teat dipping. In most cases, teat spraying and dipping are manual processes requiring high labour input which leads to expense and time. Further, the effectiveness of the operation is dependent on the diligence of the operator—which may be variable.
To address these issues, automated teat spraying systems have been developed, however these have problems associated with them.
One type of automated spray system is situated in the race and can spray the cow either prior to or after the cow enters the milking shed. The spray nozzles are located on the floor of the race and are triggered by a sensor.
However, in this situation the cow is moving in relation to the spray unit thus, dependent upon the speed of the cow movement, the delivery of the spray can vary. This mistimed spray can result in uneven coverage, insufficient spray delivered or even a complete miss.
Further, as a consequence of the spray unit being floor mounted a significant volume of disinfectant is required to be used to ensure that the spray reaches teats.
Yet another problem associated with race spray systems is the effect of wind drift which can cause some or all of the disinfectant solution to miss the teats. An alternative to spraying teats in the race is to spray while the cows in the milking shed.
Currently, there are three main types of milking sheds utilised.
One is the herringbone shed whereby there is a number of stationary bales surrounding a milking pit from which the farmer places the teat cups on to the cows.
Another system is the use of rotary platforms whereby the cow enters the platform which rotates (usually one full rotation per milking cycle—depending on the cow), and then exists the platform.
Finally, robotic milking systems have been gaining in popularity, particularly in Europe. This system has only one set of teat cups which animals approach in accordance with the animals whim, rather than being herded for mass milking as with the other systems.
As you can see, the position of the cow is known in relation to all of these systems. However, existing devices have a fixed location spray head or the floor which unfortunately is usually positioned too far away in relation to the cows teats making it difficult to spray the cows teats successfully.
With the herringbone system, or a rotary system, it could be possible to have individual spray heads in each bale. However this is an expensive means in terms of set up costs and maintenance.
New Zealand Patent Number 502723 describes how an existing rotary platform can be modified by cutting apertures in front of the platform. The spray head is then mechanically timed to rise through the aperture and spray the teat/udder.
Modifying a rotary platform to include this device requires the apertures to be cut in the platform and the mechanical system installed during manufacture for new installations. A retrofit installation into an existing dairy shed would require apertures to be accurately cut into the platform and the mechanical timing system installed. As can be appreciated, this exercise is likely to be too expensive and time consuming.
Further, by having spray heads located at or just above the floor of the platform can still have problems as described previously if poor coverage or excess amounts of sanitizer is being used due to the distance between the teats and the spray nozzle.
It is therefore an object of the present invention to address the above problems or at least to provide the public with a useful choice.
All references, including any patents or patent applications cited in this specification are hereby incorporated by reference. No admission is made that any reference constitutes prior art. The discussion of the references states what their authors assert, and the applicants reserve the right to challenge the accuracy and pertinency of the cited documents. It will be clearly understood that, although a number of prior art publications are referred to herein, this reference does not constitute an admission that any of these documents form part of the common general knowledge in the art, in New Zealand or in any other country.
Throughout this specification, the word “comprise”, or variations thereof such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated element, integer or step, or group of elements integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.
Further aspects and advantages of the present invention will become apparent from the ensuing description which is given by way of example only.